I noticed a post a few days ago about the fact that one can make hydriodic acid by using tartaric acid on potassium iodode, forming insoluble potassium tartrate leaving the HI ions alone in the solution. This is incredibly simple, does it really work like that? I presume that the reaction cannot be done with the K-Tartrate still in the bottom there... or can it? for one thing the tartrate is undissolved, two, it is solid hydrated ionised salt conjugate, and three, it's not benzylic hydroxyls on tartaric acid, it is a dihydroxy acid. If it were possible to simply react without filtering that would be nice. The amount of crap in most cooks, other than the reagents is pretty high anyway.
All the methods for producing reactive phosphorous from raw materials are inaccessible to the mere mortal. I'm just curious to know if a more accessible reducing agent can be used to reduce phosphoric acid. Like, i notice in an old text transcribed on another thread that mercury bichloride (i believe it was HgCl2) with limited air, with white phosphorous... it confused me totally actually, but it did trigger a thought in my head. Is there something that is a stronger reducer that we can use to condense out one or two of those oxygens we are not wanting on the phosphoric acid?
Is there something other than phosphorous, that promotes the ionisation of iodine into the acid, that can be present during the reaction? I know that as far as is known there isn't. However, if a way can be found to reduce phosphoric acid back to the hypo, or at least phosphorous acid, this would be fine as phosphoric acid is everywhere. Another reagent which reacts phosphoric acid in situ would be great if there was no side products caused by this (which i think is likely). Like, something like adding a small amount of zinc metal to the HI or something like that, something which will catalyse the reduction of the HI again.
Perhaps the gradual addition of GAA or conc phosphoric acid could counterbalance the de-saturating effect of the generated water and loss of HI ions as iodine, gobbling up the water as it is formed, keeping it clear of the remaining active and concentrated HI. If the tartrate salt is not problematic to the reaction it could do the job too, adding more ions to the cooking solution would drive iodine out and fill the condenser... or coat the cold trap (maybe a coldfinger would be the way to do it)
imho, a method to do away with phosphorous is sorely needed, it is becoming the harder to aquire sufficient than even the precursor now. HI reactions are useful for a lot of other things so development of HI reaction systems is a worthwhile pursuit for bees i think.
